Emerging properties and applications of spin crossover nanomaterials

Spin state switching of metal complexes by visible light or hard X-rays

“…), these compounds have gained a lot of interest due to their potential for applications in spintronics, display devices and sensors. [7][8][9][10][11][12] Despite their great potential, very few technical applications including such materials are known at presentpossibly limited by problems in handling such complexes on a molecular level (e.g. addressing single molecules, chemical instability, etc.).…”

“…[7][8][9] Solving these issues is currently an important topic in the field of nanoscience with the aim to customize future spintronic devices. [13][14][15][16] In this respect, electromagnetic or even electric excitations are considered the most promising stimuli, compared to thermally induced SCO.…”

A Two‐in‐one Pincer Ligand and its Diiron(II) Complex Showing Spin State Switching in Solution through Reversible Ligand Exchange

“…In the first step, deprotonation of A by nBuLi (2.5 equiv) followed by the addition of di(tert-butyl)chlorophosphine (1 equiv) resulted in the formation of B in 90 % yield. Repeating the sequence with 4.5 equivalents of nBuLi for deprotonation in the second step followed by the addition of another equivalent of di(tertbutyl)chlorophosphine gave the desired proligand HL in 42 % Reaction of HL with two equivalents of Fe(OTf) 2 -(CH 3 CN) 2 (OTf = triflate) in acetonitrile and in the presence of 10 equivalents of NEt 3 (for capturing the pyrazole-Nbound proton) gave a reddish yellow solution from which light yellow crystalline LFe 2 (OTf) 3 (CH 3 CN) (1) could be isolated in 60 % yield. 1 is an air sensitive complex that is soluble in common organic solvents.…”

“…[1] It is most frequently observed for iron(II) complexes, and its relevance ranges from the role of metal ions in biology [2] to magnetic device applications. [3] Spin crossover is mostly observed for bulk materials in the solid state, in which intermolecular cooperative effects play important roles for achieving complete, often abrupt, and in some cases even hysteretic highspin/low-spin transitions in response to external perturbations, such as irradiation with light or changes in temperature or pressure. [4,5] In contrast, spin transitions of molecules in solution are relatively rare, and they are usually characterized by gradual SCO following a Boltzmann distribution and resulting in a spin state equilibrium because of the lack of any cooperativity.…”

Metal Substitution Effect on a Three-Dimensional Cyanido-Bridged Fe Spin-Crossover Network

“…This phenomenon can be modulated by various physical and chemical stimulations (e.g., light, pressure, temperature, vapor molecule, and metal substitution), and it has potential for sensor and memory applications [14,15]. To control the spin-crossover behavior, the metal substitution effect on the spin-crossover behavior for some Fe II spin-crossover materials has been investigated [16][17][18][19][20][21][22][23][24][25].…”